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A kernel driver is necessary to initalize the tablet and translate hardware-specific protocols into standard input events. We contribute patches directly to the Linux kernel, as well as maintain an out-of-tree kernel module that enables old kernels to work with many newer tablets.

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the concept of magic numbers goes back to unix and pre-dates the use of file extensions.
The original idea of the shell was that all 'executable' would look the same - it didn't matter how the file had been created or what program should be used to evaluate it. The shell would look at the contents of the file and determine the appropriate file. Microsoft came along and chose a different approach and the era of file extensions was born. Then to make things 'nicer' for users microsoft chose to 'hide' these extensions and the era of trojan files which look like they are of one type but really have a different extension and are processed by a different file was born.

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“The number of moving parts is so vast, and several of them are under the control of different groups. There’s no way you could ever pull it together into an integrated system in the same way as you can in a single commercial product with, you know, a single maniac in the middle.”

While there are indeed many moving parts modern Version Control Systems take care of that properly and automatically. The idea of a Benevolent dictatorship dictating the course of the software is not wrong, but it's been shown that it limits the software itself, no matter how smart or good the dictator is, he/she will never be able to think about every aspect and possible applications of the software. And considering this is a tool for research and experimentation, limiting the tool on purpose is not a very good idea, if you ask me. EVEN THEN, an open-source model leaves space for a Benevolent dictatorship (just as Linux and Google does for many of its FOSS projects), so that isn't really an argument against an open-source non-commercial developing model, in the worst case scenario.

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1) <hex_major><hex_minor> device number in hexadecimal represents itself
* no leading 0x, for example b302.
* 2) /dev/nfs represents Root_NFS (0xff)
* 3) /dev/<disk_name> represents the device number of disk
* 4) /dev/<disk_name><decimal> represents the device number
* of partition - device number of disk plus the partition number
* 5) /dev/<disk_name>p<decimal> - same as the above, that form is
* used when disk name of partitioned disk ends on a digit.
* 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
* unique id of a partition if the partition table provides it.
* The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
* partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
* filled hex representation of the 32-bit "NT disk signature", and PP
* is a zero-filled hex representation of the 1-based partition number.
* 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
* a partition with a known unique id.
* 8) <major>:<minor> major and minor number of the device separated by
* a colon.

this is all possible valid formats passed to root= option in linux boot command line

If zone reclaim is switched on, the kernel still attempts to keep the reclaim pass as lightweight as possible. By default, reclaim will be restricted to unmapped page-cache pages. The frequency of reclaim passes can be further reduced by setting /proc/sys/vm/min_unmapped_ratio to the percentage of memory that must contain unmapped pages for the system to run a reclaim pass. The default is 1 percent.

This is a percentage of the total pages in each zone. Zone reclaim will only occur if more than this percentage of pages are in a state that zone_reclaim_mode allows to be reclaimed.

If zone_reclaim_mode has the value 4 OR'd, then the percentage is compared against all file-backed unmapped pages including swapcache pages and tmpfs files. Otherwise, only unmapped pages backed by normal files but not tmpfs
files and similar are considered.

There is a knob in the kernel that determines how the situation is to be treated in /proc/sys/vm/zone_reclaim. A value of 0 means that no local reclaim should take place. A value of 1 tells the kernel that a reclaim pass should be run in order to avoid allocations from the other node. On boot- up a mode is chosen based on the largest NUMA distance in the system.

There has been some recent work in making the scheduler NUMA-aware to ensure that the pages of a process can be moved back to the local node, but that work is available only in Linux 3.8 and later, and is not considered mature.

Stamped2 KNL nodes are already running 3.10, so this is likely available.

The active memory allocation policies for all memory segments of a process (and information that shows how much memory was actually allocated from which node) can be seen by determining the process id and then looking at the contents of /proc/<pid>/numa_maps.